[mythtv-users] Audio - hiss (Buzz)

[Scott Croft]

On Mar 14, 2006, at 7:05 PM, Scott Croft wrote:

> On Mar 12, 2006, at 8:01 PM, Scott Croft wrote:
>
>
>
>
> Yes it is more of a Buzz/hum and not a hiss, I guess I did not use
> the right
> audio term!
>
> The hum is not present at all until one of two things happen.  I
> short/ground the left or right channel going to the line in, or I
> plug the
> sound card line in to the TV card line out with the patch cable.
> After
> reading and asking question I agree with you that when I touch or
> ground the
> line in I should here the buzz.  The problem is that I get the same
> results
> when I connect the TV card to the line in on the onboard audio
> (also get the
> TV audio).  Both left and right channels have the buzz.
>
> I think that I tried the mixer settings you describe (think I read
> something
> to the same effect) and could not get any sound at all with
> settings like
> that.  Not sure about this.
>
> Since my last mail I have added a PCI sound card and disabled the
> onboard
> audio in the bios.  This works with no trouble.  Not the solution I
> wanted,
> but it works.  I am using all the same settings and hardware with the
> exception of the onboard audio.  I guess this tells me that my
> brand new
> onboard audio is broken, or I have some type of grounding problem
> with the
> PC??
>
> Again thanks for the input, it is much appreciated.  I am moving on
> to get
> the remote control working, and the s-video output to fill my
> entire TV
> screen.
>

Are you using the same patch cord from the cap card output to the
audio input ?? It's possible that you have a bad cable, actually more
likely than a bad mobo sound setup.

Are you sure that you pushed the cable into the on-board input and
the cap card output firmly ??

Are you sure you were using the proper connectors (ie: 3-conductor
connectors at both ends, not a 3-c to 2-c cable).

Are you sure you were going into a "line in" on the mobo and not a
"mic in" ??

All of the above could result in the symptoms you describe.
_______________________________________________

I am using the same patch cord, and had tried another patch cord at several
points in this processes.

I must have pluged and unpluged the cables about 100 times testing different
combinations, so I am reasonably sure that all was pluged in well.

The patch cable is a 3 conductor cable with male mini-sterio conectors on
each end.  No conductivity (shorts) between any of the three wires or
connectors as per my fluke meter.

I am sure I had the patch cable ran into line in on the audio card.  I also
switched to the mic port while switching the mixer controls to look for the
input on that connection.  Same problem with the buzz on the mic as with the
line in as each was tested.  At one point I cut up a CD audio cable and
attached it to the aux audio port on the mother board and wired it into a
old sterio jack that I pluged into the line out on the TV card.  When I
picked aux as the capture device and muted it I still got the buzz along
with the sterio tv audio signal.  The aux / CD inputs are a good ways from
the other audio input ports on the mother board.

I really do not have any other ideas on how to fix this issue.  With the new
PCI audio card I can use about any settings I want for volume on the master
or PCM and have no issues with any buzz.